Racing pundit John McCririck was rushed to hospital after falling ill at a racecourse from stress brought on by a falling out with his former employer, his wife said.
The 72-year-old complained of feeling unwell during the first day of the Cheltenham Festival yesterday and was taken to hospital by ambulance.
The veteran broadcaster was expected to be kept in Cheltenham General Hospital overnight for further tests to be carried out, his agent said.
McCririck's wife Jenny blamed her husband's illness on the stress of an ongoing disagreement with Channel 4, the Daily Mirror said.
"Look at the stress from Channel 4," she told the newspaper. "He was perfectly OK, he had a check up two weeks ago, but Channel 4 have done this to him."
Channel 4 dropped McCririck from its racing coverage when it unveiled its new presenting team, headed by Clare Balding. In January McCririck announced he was to sue the broadcaster for £3 million, claiming it axed him from its racing coverage because he was too old.
The presenter - known for his bling, sideburns and deerstalker hat - is no stranger to controversy. Known for his outspoken views, he appeared in Celebrity Big Brother in 2005 and famously refers to his wife as the Booby.
Speaking at the course on Tuesday, a friend of McCririck's said: "John felt unwell at the races and will be kept in overnight for assessment."
A spokesman for the hospital said: "We are aware that John McCririck has been admitted and his condition is stable."
His agent said: "John fully intends on being back on the course tomorrow."